Can Any Fool Swap an 8.8 Rear End into an XJ?

Let's find out. I'll be the fool trying to replace a Dana 35 in my 1998 Cherokee with a Ford 8.8 rear end with disc brakes, 4.10 gears and limited slip out of a 2000 Ford Explorer.

This may seem like a simple task for a lot of you, but I am less than qualified to complete this axle swap. I've never opened up a rear end, pulled an axle shaft or been particular handy with a cutting wheel. I'm sure this process will be a slow, painful learning experience.

Rather than clog the forum with my idiotic questions, I'll just put them all in this thread.

First, I went hunting for the axle combo I was looking for. I had to look at about 30 Exploders in two junk yards before I found the right combination. Factory 4.10 gears seem to be somewhat rare in these axles, but I wanted to avoid the cost of regearing to match the front. Even though the limited slip is reportedly weak in these axles, I wanted it to hold me over until I can afford an ARB.

Unfortunately, the one I found had already been molested in the junkyard. I scraped up the pieces and took it home. It seems to be in good shape.

Cost: $320 at Pick Your Part by the time I paid for the axle, brake calipers, core charges, environmental fees, recycling fees, sales tax, etc. Ouch



I kept as much of the brake hardware as I could, just in case.

At home, I discovered that all the parts were accounted for except for one clutch plate. That's fine, I was going to order a fresh clutch pack anyway. I found one for $55 shipped on ebay.



I still need to acquire u-bolts, spring perches, shock mounts, one missing brake disk, parking brake connectors, a yoke adapter. I'm trying to keep this as cheap as possible, but I'm already at $375. Please don't tell my wife.

While I'm waiting for those parts, it's time to remove the brake lines, re-assemble the carrier and start grinding off the factory brackets.

Not sure if you are content with where you're at with your lift. But one thing I would consider are UBE's UBE >U-bolts figure since you are going to have perches mounted anyways, why not? Usually add about .5" depending on what you get.

Interesting, but I'm actually concerned that the larger diameter tubes and taller spring perches on the 8.8 will increase the lift too much in the rear. I was thinking about using shorter shackles to compensate.

You got this, it may end up costing more than you expected. But you've got this, be extra careful at the stage of welding on your new perches, that's the hardest part. Measure twice, tack once, then ask someone to double check your setting. When in doubt, post up, even if its in the chapters.

If you're carefull, you can ever reuse the oem perches to save some cash, however axle swap budgets tend to balloon quickly.

Good luck

xcm said:

If you're carefull, you can ever reuse the oem perches

Click to expand...

Careful is.... not my middle name. You should see what I did to the shock mounts with a cutting wheel. There is no hope of saving anything.

Actually, that brings me to the first dumb question. Is there a technique to grinding these old welds smooth? Do I just just run the wheel back and forth while trying my best not to dig into the housing?

Travis,

Bring it over (you can grab my pickup so not to put it back into your jeep) and you can do this with us, if you want.

Yes, use a flap disc (easier on your hands) and grind back and forth while watching to not dig too far into the housing.

You'll want new u-bolts of the proper diameter. Don't get them at a local auto parts store, the quality is not great. Deaver Spring in Santa Ana can make you a set up of high quality grade 8, I like to get them made in 5/8" bar stock.

Set your new perches on the axle, and set it under your vehicle. Lower it down until the springs just touch the perches. Bolt the u-bolts up snug, but not tight, and then lower your rigs weight onto the rear end. Using a hammer, tap the third member near the pinion up or down to align your pinion angle. Once that is in place, tack weld the perches in.

Figure out shock mounting locations, and tack the shock mounts in place. Lift the weight back off of your vehicle, unbolt the u-bolts, and lift the jeep back off of the axle. Weld everything into place.

Reassemble, attach brakes and bleed them.

It should take an afternoon.

Cal's got it right. I've had pinion angle issues when not fully tightening the ubolts though... spring pack compresses a little unevenly front to back and the result is that the pinion angle changes between snug and tight on the ubolts. So I just tighten it fully every time now and loosen it a bit before adjusting each time till I get it spot on.

You can get spring perch/ubolt/shock mount kits from ruffstuff, their parts are great quality.

kastein said:

Cal's got it right. I've had pinion angle issues when not fully tightening the ubolts though... spring pack compresses a little unevenly front to back and the result is that the pinion angle changes between snug and tight on the ubolts. So I just tighten it fully every time now and loosen it a bit before adjusting each time till I get it spot on.

You can get spring perch/ubolt/shock mount kits from ruffstuff, their parts are great quality.

Click to expand...

With the vehicle weight on it, that shouldn't happen?

I know, right? That's what my logic was. And then I learned from the school of hard knocks.

Just thought of something, there is a good chance that the vehicle in question being a spring-under MJ had something to do with it - the springs start out with a hell of a lot more arch to them, as I'm sure you're aware, and are still arched at ride height. Versus an XJ where they're nearly flat at ride height, at least on a stocker. I hadn't even considered that till just now. Still I'd say get everything adjusted nicely with it snug, then tighten it fully once and check to make sure everything stayed aligned before full welding. Better safe than sorry IMO.

Thanks Cal. I will hit you up once I get everything prepped.

The 8.8 swap kit from RuffStuff looks like a good deal.

Wouldn't a grinding wheel work better on the bulk of the material, followed by a flap disc for clean up? I've never tried a flap disc so I wouldn't know.

Not really, no. A flap disc removes material faster, and doesnt vibrate as much in your hands, so its not as hard on you.

Flap discs don't last as long, but we buy them in bulk from Roarke supply with the discount, so don't worry about that..

x2 on the flap discs, I haven't used my grinding disc in years because of them.

Consider a grinding wheel to be a hatchet, and the flap wheel disc is one of those Japanese double cut saws.

Flap wheels come in different grits so you can adjust your material removal to what you need. Which is very useful.

Cal is also very correct about hand comfort, the grinding wheels bounce around and get annoying after a while.

travisk said:

Interesting, but I'm actually concerned that the larger diameter tubes and taller spring perches on the 8.8 will increase the lift too much in the rear. I was thinking about using shorter shackles to compensate.

Click to expand...

That's what I ran into. I surprisingly ended up with another .5"-.75" of lift. I needed it.

you can get a lot closer than that with a cutoff disc and it will be way faster than a flap disc or a grinding wheel.

just be careful and cut small sections out.

I was able to get mine almost completely gone without using the flap disc.

then use a flap to clean it up.

What's a cutoff disc? I just ground the whole spring perch into dust.

.......

next time come over and use the plasma cutter.

It was a joke.

i know.

still though, the plasma's sitting there.